Ixxiy PEOCEEDINGS OP THE GEOLOGICAL SOCIETY. 



trodiiced the cooperation of the ocean, and with it the production of 

 granite, and afterwards of the stratified formations. 



In the work already referred to, by M. Priedrich Mohr*, a chapter 

 is devoted to the " Geology of the Heavens," and an interesting sum- 

 mary is given of the chief points of comparison of the meteorites with 

 terrestrial rocks ajid minerals. But, although agreeing with other 

 authors on the details of composition and on the phenomena of their 

 occurrence, Mohr is entirely at issue with the opinions which have 

 been above cited as to their origin. In their crystalline composition, 

 in the mixture of different substances, and in the structure of several 

 of them, he sees throughout the operation of watery solution. " The 

 entire aspect of a meteorite," according to him, "■ speaks against 

 fusion ; " and as in the earlier portion of his work he has battled for 

 the production by the wet way alone of all the silicates, even in- 

 cluding olivine and augite, so in dealing with the meteoric silicates, 

 he simply refers them to a similar origin. If, then, we lay suffi- 

 cient stress on the very exceptional cases already quoted, in which 

 carbonaceous matter has been shown to occur in meteorites, we 

 might conclude, from the indication thus obtained of such carbo-hy- 

 drogen minerals as ozokerite, idrialite, &c., that there must have ex- 

 isted in the original cosmical body some such organisms as the plants 

 of the earth, and, going a step further, that it was by their agency 

 that the chemical reductions were effected of which we have evi- 

 dence in the meteoric irons. So many, however, of Mohr's dicta 

 are flatly contradicted by the results of Daubree's experiments, that 

 the impression which might have been produced in regard to some 

 aspects of our science by so confident and clever a treatise as the 

 ' Greschichte der Erde ' will at once be greatly modified. 



Thus, gentlemen, I have ventured to place before you some of the 

 newest views on a limited branch of our science ; and I trust that 

 the selection of a single topic may be justified by the evidence which 

 I have adduced of its fundamental importance, and of the connecting 

 link which it appears to supply between the history of our own 

 globe and that of other members of oiu^ solar system. It is not to be 

 denied that the opinions of authors and experimenters who have 

 recently been at work on the subject are extremely divergent. But 

 it appears to me for that very reason the more desirable to place side 

 by side their opposite conclusions, and thus by degrees to eliminate 

 whatever may be one-sided, ill-founded, or not adaj)ted to the con- 

 ditions of the problem. There must always remain in geology, by 

 the side of much that can be determined as actual fact, a large 

 domain in which speculation will have ample scope ; and it is in 

 this latter region more especially that we have need to exercise 

 caution, readiness to deal fairly with new views, and a deference to 

 other men's opinions in the pursuit of that truth which it is the 

 object of geologists to attain. 



^ ' Geschichte der Erde,' Bonn, 1866. 



